Phone going dead alot faster all of a sudden!?!?

[Redx]

I have had this as my work phone of a while now. Its a decent basic phone and i dont mind it. But here in the past 2 weeks my phone seems to go dead ALOT faster on its own now. Before on the weekend I could leave it off the charger all weekend without using it and it was fine by sunday when I go to recharge it. But now it goes dead fairly quick in maybe 24 hours without even using the phone.

I checked the battery usage and its mostly cell standby.

Any ideas? Or what I can do to help this? I would hate to have to buy a new battery

 

[LifesGoodPhoenix]

Sorry for late reply.
on stock charge fully and reboot.
if have custom recovery fully charge and wipe batt stats.